legendary-fiesta

iOS sample app shows how to do a terms of service screen that user must accept.

The point of this mini app is to illustrate how to determine the initial app screen programatically.

See AppDelegate.swift and AcceptViewController.swift.

AppDelegate.swift:

Add 2 variables to keep track of the 2 view controllers we are interested in.

var mainViewController: ViewController?
var acceptViewController: AcceptViewController?

Then, inside this function:

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {

Load the storyboard:

    let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)

Load and store the view controllers:

    mainViewController = mainStoryboard.instantiateViewController(withIdentifier: "MainView") as? ViewController
    acceptViewController = mainStoryboard.instantiateViewController(withIdentifier: "AcceptView") as? AcceptViewController

Check to see if the user had previously accepted the terms of service.

    let isAccepted = UserDefaults.standard.bool(forKey: "isAccepted")

Then decide which view controller to show.

    if isAccepted == false {
        switchToAcceptViewController()
    } else {
        switchToMainViewController()
    }

2 helper functions in AppDelegate to switch between view controllers.

func switchToMainViewController() {
    //mainViewController?.selectedIndex = 0 // only needed if the main view controller is a tab view
    self.window?.rootViewController = mainViewController
    self.window?.makeKeyAndVisible()
}
func switchToAcceptViewController() {
    //mainViewController?.selectedIndex = 0 // only needed if the main view controller is a tab view
    self.window?.rootViewController = acceptViewController
    self.window?.makeKeyAndVisible()
}

In AcceptViewController.swift

If the user presses the accept button, remember that choice and switch to the main view controller.

    @IBAction func acceptAction(_ sender: Any) {
        UserDefaults.standard.set(true, forKey: "isAccepted")
        let appDelegate = UIApplication.shared.delegate as! AppDelegate
        appDelegate.switchToMainViewController()
    }